The retrofit of a machine means the professional adaptation of carrier machines and attachments to new tasks, materials, or boundary conditions. In concrete demolition, special demolition, interior demolition, rock demolition and tunnel construction, as well as natural stone extraction, flexible retrofitting is crucial to work precisely, with low vibration, and cost-effectively. A recurring practical example is switching from a breaker hammer to a concrete demolition shear for selective deconstruction, or switching to stone splitter and concrete splitter when low-noise and controlled work is required in sensitive zones. The following sections explain how the retrofit is technically planned, safely implemented, and qualitatively evaluated—referencing attachments and power units from Darda GmbH without promotional character.
Definition: What is meant by machine retrofit
A machine retrofit is the systematic adaptation of a carrier machine—such as an excavator, demolition robot, or carrier sled—as well as the power supply and control, to be able to use different attachments or meet changed work requirements. This includes mechanical interfaces (mounting, adapter plate, quick coupler), hydraulic parameters (working pressure, oil flow, return line), electrical/control signals, as well as occupational safety and documentation obligations. Typical reasons include switching to concrete demolition shear for selective concrete demolition, adapting to stone splitter and concrete splitter in areas with vibration or noise restrictions, switching from standard to special shears (combination shears, steel shear, tank dismantling) or integrating a hydraulic power pack when the carrier machine does not provide the required oil flow or system pressure.
Planning and sequence of the retrofit
Technical planning begins with a clear task analysis (construction materials, reinforcement, component thicknesses, desired cutting or splitting results, boundary conditions such as noise, dust, vibrations). This is followed by the technical assessment of the carrier machine (weight class, load capacity, hydraulic connections, permissible system pressure, maximum flow rate, return routing) and of the target tool (required pressure/flow, weight, center of gravity, single/double-acting operating mode). From this arise the need for adapter plate or quick coupler, any changes to hydraulic hose lines, couplings and case-drain lines, the selection of a suitable hydraulic power pack, and the definition of the control logic (fine controllability, proportional or stepped). The assembly sequence includes mechanical mounting, hydraulic hose routing with pressure- and flow-rated lines, a structured leakage test and functional check, setting the working pressures, running-in under load, and documented commissioning including operator briefing. Especially with concrete demolition shear, sensitive controllability is important for clean biting of concrete while protecting the reinforcement; with stone splitter and concrete splitter, correct pressure provision and safe wedge guidance take priority. In addition, operating manuals must be observed, hazard analysis updated, and markings supplemented.
Hydraulics and power supply
The hydraulics are the heart of the retrofit. They determine whether a machine can operate an attachment efficiently, safely, and durably.
Oil flow, pressure, and control
Every tool requires matched system pressure and suitable oil flow. Insufficient flow slows cycle time; excessive flow causes unnecessary heating. Sensitive control improves quality in precision demolition. For concrete demolition shear: high crushing force must be applied in a controlled manner to open components without overloading the carrier machine. For stone splitter and concrete splitter, a reproducible pressure ramp is critical so splitting wedges seat evenly and intended fracture lines develop.
Return, case drain, and filtration
A sufficient, preferably low-pressure return line protects seals and reduces heat. Case-drain lines—where required—must be correctly sized and routed without pressure. Effective filtration prolongs the service life of valves, cylinders, and couplings.
Hydraulic power packs in concert
If the carrier machine does not deliver the required pressure or flow, external solutions such as integrated hydraulic power units can be added. This supply enables operation of power-intensive tools or the parallel use of multiple consumers. For splitters and special shears, stable pressure, constant delivery rates, and easily accessible quick coupling points are decisive.
Mechanical interfaces and carrier machine
Mechanical compatibility is a prerequisite for safe operations. Adapter plates, pin diameters, widths, and quick coupler systems must fit exactly.
Weight, center of gravity, and load capacity
The operating weight of the attachment affects stability. The load charts of the carrier machine must be observed. Concrete demolition shear with large jaw openings requires sufficient lift force even with the boom extended. Splitter systems with cylinder units and wedges change the center of gravity, especially during boom work or on carrier sleds in tunnels.
Mounting and protection
The mounting should be torsion-resistant. Guard plates, hose protection, and guidance aids reduce damage. For indoor work—such as interior demolition—compact mountings are advantageous for precise maneuvering.
Application fields and typical retrofit scenarios
Depending on material, component thickness, and boundary conditions, different tools are advantageous. Some typical switches in practice:
- For concrete demolition and special deconstruction: switch from a breaker hammer to a concrete demolition shear for controlled biting, lower vibrations, and selective separation of concrete and reinforcement.
- Interior works and cutting: use combination hydraulic shears or Multi Cutters when trapezoidal sheets, structural sections, pipelines, and mixed materials are involved.
- Rock excavation and tunnel construction: switch to stone splitter and concrete splitter or a rock wedge splitter when low-vibration and low-noise work is required—e.g., near sensitive infrastructure.
- Natural stone extraction: splitting technology to produce defined fracture edges and raw blocks without creating large-scale microcracks.
- Special operations: tank dismantling or steel shear when contaminated vessels, pipelines, or thick-walled steel components need to be segmented.
Quality criteria and result evaluation
The quality of a retrofit is reflected in the result on the component and in the process.
Work pattern and component quality
With concrete demolition shears, clean demolition edges, targeted opening of components, and controlled handling of reinforcement bars matter. With splitters, a reproducible split pattern with minimal rework is decisive.
Performance, cycle times, and energy efficiency
Cycle time per cut/split, hourly throughput, and fuel or power consumption are key metrics. Proper hydraulic tuning reduces heat losses and protects components.
Safety and regulations (general, non-binding)
General notes, not legally binding: Before start-up, observe the operating manuals of the components, update the hazard analysis, and define protective measures (e.g., barriers, protective clothing). Pressure tests, leakage tests, and functional tests must be documented. For attachments with cutting or splitting action, the danger zone must be clearly defined. In noise-sensitive areas, noise emission limits must be observed. Test intervals and maintenance requirements must follow manufacturer specifications and applicable rules of technology.
Checklist for the retrofit in practice
- Define the task: material, target quality, boundary conditions (noise, vibration, dust).
- Check the carrier machine: load capacity, hydraulics (working pressure/flow), interfaces, power supply.
- Select the tool: concrete demolition shear, stone splitter and concrete splitter, combination shear, steel shear, tank dismantling, Multi Cutter.
- Plan the mechanics: adapter plate/quick coupler, pins, protection for hoses.
- Design the hydraulics: hose lines, quick couplings, return line, case drain, filtration, if necessary hydraulic power pack.
- Assembly and start-up: leakage test, pressure setting, function test without load, running-in under load.
- Documentation: parameters, test protocol, operator briefing.
- Monitor the start phase: cycle times, temperature, freedom from leakage, work pattern.
Typical failure patterns and avoidance
- Unsuitable flow/pressure: leads to slow movement or overload. Solution: measure and adjust parameters, integrate power pack if necessary.
- Insufficient return line: heat build-up, seal damage. Solution: increase return cross-section, use a low-pressure return.
- Incorrect mounting/adapter: play or misalignment. Solution: dimensionally accurate adapter plate, correct pins.
- Insufficient fine control: jerky movements. Solution: tune valves, use proportional control.
- Underestimated load capacity: instability. Solution: observe load chart, check tool weight and center of gravity.
Maintenance, training, and documentation
After the retrofit, regular inspections ensure readiness for use: retighten bolted joints, check hose bundles, monitor oil condition, lubricate moving parts. Training fosters operator finesse—especially with concrete demolition shears and splitters, where precise approach and holding determine quality. Lean, traceable documentation of settings (working pressure, flow, valve configuration) shortens future retrofit times.
Practice-oriented decision aids
For selective deconstruction of massive reinforced concrete components, retrofitting to a concrete demolition shear is suitable when vibrations must be minimized and reinforcement must be selectively exposed. If low-noise and low-vibration methods are paramount—e.g., in inner-city zones, at sensitive structures, or in tunnels—stone splitter and concrete splitter are a robust option. For mixed materials and metallic inserts, combination shears, steel shear, tank dismantling, or Multi Cutters can be considered. The key is tight integration of the mechanical interface, matched hydraulics, and a control logic that brings force into the component in a controlled manner.